From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.ciao.gmane.io!not-for-mail From: Stefan Monnier Newsgroups: gmane.emacs.devel Subject: Re: Is Emacs buffer scroll/redisplay slow? Date: Mon, 20 Jan 2020 08:20:41 -0500 Message-ID: References: <20200119115146.GA9172@ACM> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="ciao.gmane.io:159.69.161.202"; logging-data="93958"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.0.50 (gnu/linux) Cc: Alan Mackenzie , Emacs developers To: Fabrice Popineau Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Mon Jan 20 14:21:45 2020 Return-path: Envelope-to: ged-emacs-devel@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1itWzw-000OFE-Of for ged-emacs-devel@m.gmane-mx.org; Mon, 20 Jan 2020 14:21:44 +0100 Original-Received: from localhost ([::1]:36302 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1itWzv-0005kW-RW for ged-emacs-devel@m.gmane-mx.org; Mon, 20 Jan 2020 08:21:43 -0500 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:60192) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1itWzA-0005JT-Jg for emacs-devel@gnu.org; Mon, 20 Jan 2020 08:21:00 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1itWz5-0003q1-Kd for emacs-devel@gnu.org; Mon, 20 Jan 2020 08:20:55 -0500 Original-Received: from mailscanner.iro.umontreal.ca ([132.204.25.50]:52895) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1itWz5-0003p1-Ds for emacs-devel@gnu.org; Mon, 20 Jan 2020 08:20:51 -0500 Original-Received: from pmg3.iro.umontreal.ca (localhost [127.0.0.1]) by pmg3.iro.umontreal.ca (Proxmox) with ESMTP id 2CDED4407FB; Mon, 20 Jan 2020 08:20:50 -0500 (EST) Original-Received: from mail01.iro.umontreal.ca (unknown [172.31.2.1]) by pmg3.iro.umontreal.ca (Proxmox) with ESMTP id C50E94407F1; Mon, 20 Jan 2020 08:20:48 -0500 (EST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=iro.umontreal.ca; s=mail; t=1579526448; bh=u5FDb5O7lyjxyRrI5FU58GBS3B9BtCFnZW5bDdjgABM=; h=From:To:Cc:Subject:References:Date:In-Reply-To:From; b=R52iQbSMAvBl9wAcdZe/DjzB8AIyfH8QRb+uMcZv0GdVo5J1Mfu4RvHHCSXVrdA85 1d9SYfRG8VFfrL6KFaFT7Lqw/02isaKC7LCswnsZ1vK1FrgsHMJlaUoK+iHsJ0+WQR ux9f1QHqrBGwgEDz4hnhiJbgNx5SB+uSSLljRASp8cvIneNfQ3WFqN2w7znJgWo/yh up+5ckyzsvmthy08sn4lIVt/cNlJXv6iwI0+fQBJu+tL0F4Xt/YGU2jSLoZNz3OP9O HbeuPX64kUT9RqzCUOmdKAlRTnKiphQEzalvRujn8yFInKpoXTrgj1IQqz/52K5uQs AyEoHN8T1wDqQ== Original-Received: from pastel (unknown [45.72.156.100]) by mail01.iro.umontreal.ca (Postfix) with ESMTPSA id 86F35120622; Mon, 20 Jan 2020 08:20:48 -0500 (EST) In-Reply-To: (Fabrice Popineau's message of "Mon, 20 Jan 2020 01:23:22 +0100") X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 132.204.25.50 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.io gmane.emacs.devel:244411 Archived-At: >> If Emacs is slow in such a test, you'll notice because it will stop >> refreshing the display at times (hoping that skipping the redisplay time >> will help it keep up with the repeat rate). > If I posted this, it is because looking at it, the cursor was like > jumping from line to line, but it doesn't seem steady. Actually, > I changed some setting to get a faster autorepeat and emacs keeps up > when the time is down to 16s for 1000 lines, more than twice as fast. Ah, now you're talking! Then yes, we have a speed problem. Usually this depends on the minor&major modes involved, so the profile is the best way to start digging. Could you try and redo the profile run, but where you maximize the proportion of "line scrolling" that takes place during the time between `profiler-start` and `profiler-report`? Stefan